Looks like Gilead Sciences' (NASDAQ:GILD) investors were worried for nothing. Shares were up nearly 4% yesterday after the full data presentation of the phase 2 trial of Gilead's new HIV quad pill showed nothing remarkably new. The company had already announced  that the trial was a success last month.

The most reassuring thing about yesterday's announcement was the lack of side effects. That's especially important for one of the new components, GS 9350, which is a "boosting" agent. Gilead is testing GS 9350 separately against Abbott Labs' (NYSE:ABT) drug booster, Norvir, and any safety issues could have derailed that plan.

Investors may have been excited by the fact that 90% of patients taking the quad pill reduced their viral load to the target level, compared with 83% who took Atripla -- one of Gilead's other anti-HIV drugs -- but you need to be careful about overinterpreting the data. The trial was only designed to show that the two drugs performed the same -- that the quad was "non-inferior" to Atripla. Because of the small sample size, just 71 patients, there's a chance the better performance by the quad was due to chance. In fact, if you exclude the people who dropped out of the study or didn't get tested for some reason, the drugs performed nearly identically, with 96% and 95% of patients taking the Quad and Atripla, respectively, achieving the viral load goal.

Still, matching the Atripla should be good enough for a boost in earnings for Gilead. The company owns all four components of the quad pill, while it has to share Atripla revenue with Bristol-Myers Squibb (NYSE:BMY), which developed one of the compounds that makes up Atripla.

Cocktails of drugs have helped countless numbers of people with HIV, but it's tiresome to take many pills a day. The future of HIV treatment is an ever-increasing stacking of drugs on top of each other in one convenient pill. It's one of the reasons why Pfizer (NYSE:PFE) and GlaxoSmithKline (NYSE:GSK) established a joint venture to develop HIV drugs, and Gilead and Johnson & Johnson (NYSE:JNJ) teamed up to create a combo product of their own. As long as Gilead can continue cranking them out, it shouldn't have any problems satisfying investors' worries.

A $376 billion bubble, now that's something to worry about.

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. Pfizer is an Inside Value recommendation. Johnson & Johnson is an Income Investor selection, and Motley Fool Options has recommended buying calls on the stock. The Fool owns shares of GlaxoSmithKline and has a disclosure policy.